The invention relates to a fully extendable telescopic drawer guide for furniture components, such as drawers, work surfaces and the like, that can be extended from the body of an item of furniture, with a guide rail facing the body, a running rail associated with the extendable furniture component, and an intermediate rail arranged between these two rails, wherein rolling elements are provided which are supported in cages and which transfer the load of the extendable furniture component by way of rolling surfaces provided on the rails, and wherein at least one rotatably supported supporting roller for the running rail is provided on the front end of the intermediate rail.
Drawers and other extendable furniture components can be supported by fully extendable telescopic guides for easy movement in the body of a cabinet, so that the drawer can be fully pulled out of the body in the open position, making the content of the drawer readily accessible. This design is more complex in comparison to telescopic guides embodied as a simple telescopic rail with only a single guide rail and a single running rail, because the intermediate rail must be supported at two places, namely on the guide rail as well as on the running rail. Fully extendable telescopic guides are inherently less rigid than single guides and require a more complex design to prevent elastic deformation of the rail which would cause the faceplate of an open drawer to be displaced downward, in particular when the drawer is heavy. The individual rails for telescopic guides to be used with heavy drawers must therefore not only have an overall greater load carrying capacity, but typically also have an additional supporting roller on the front end of the intermediate rail, which employs cage-supported rolling elements to decrease the load on the mobile support in the critical open position of the drawer. Such fully extendable telescopic guides are disclosed, for example, in EP 0 834 270 B1.